Anodising

I searched and found a few threads about anodising but none of them actually came to a conclusion. Did anyone anodise anything? and is it possible to anodise my KH frame? after sandblasting all that lovely blue off of course. I am hinking of calling around and trying to get a quote, but i was just wondering if anyone has done it before and if it is worth it?

I have a friend who can do it in his backyard but he is leaving for university in a week, he got a scholorship in Sydney.

Isn’t the KH frame CroMoly? You can anodize aluminum, not steel. If it’s CroMoly it’s a steel alloy and you’re out of luck. Put a magnet on it and see if it sticks. If so, you’re not going to be anodizing it.

KH frames have been aluminum since 2005.

It is deffinitely possible to anodise any of the blue KH frames, infact the blue colour is anodising. You will need to shot blast it back to bare metal, and you will loose the KH signatures and KH 20/24/29 logo on the neck, as these are areas that are bare metal and when you anodise again they will be covered like the rest of it.

i’m interested too to know how to do that…

Well in short, go to a local anodising shop and give them some money. You can anodise at home, but you’ll need various equipment and salts, and a big tub. I’ve seen sets of this equipment for doing small parts and they’re atleast £100, compared to maybe £20 to get it done professionally it’s not really worth it, and you’d have to get it shotblast somewhere unless you have your own compressor and blast gun too.

ok so i think that i’ll probably go to a shop
thanks for the information
bobousse

i would think powdercoating woul dbe nicer though, just a thought… even pro anodising… well its not as good as a nice powdercoat…

i thought they were powdercoated

I anno all my uni’s with a blue to black fade, sometimes I’ll have another color in the “fade zone”.

Anodizing is a pretty durable coating for aluminum. It is not immune to fading over time though. It is essentially a controlled oxide coating of the aluminum that does have a measurable build up. It’ll will add about .0005-.0010" of thickness everywhere. It is important that the anodizing shop plug or mask all of the threaded holes and precision bearing surfaces so that they don’t get anodized. I’ve never looked closely at a KH frame to know just how precision the bearing surfaces are. My guess is, not enough to worry about. The thing to watch for is the threaded holes. Most anodizing shops know to mask the threaded holes but it’s still best to make sure they do this. I’ve seen some who just throw the parts in their vat and don’t pay any attention to this. The anodized finish gets into the threads and then you can’t get the bolts in. The surface is hard enough to make it a real bear to try and clean the threads up with a tap. I’ve broken taps off in the hole trying to clean up anodized threads before. And then, trying to get a broken tap out of a hole can be damn near impossible.

That’s all. Good durable finish that will fade over time and you gotta watch the precision machined areas. Pretty colors available.

sweet, thanks for the help.
i have rung around and obtained some quotes for sandblasting and the cheapest i found is about $80 an hour :frowning:
i might try get some blasting time at my old school. as for anodising, i cannot find anywhere that will do it and my anodising friend has left for Sydney.

Aside from sandblasting there’s a process I think is called “satin”, where they have a cloth on a spinner (like a buffer) which will strip any paint or previous work to the metal. Though, the frame may be awkward to work with and they may not be able to reach all the areas. Also, if you get someone who’s not really good with that machine they can ‘eat’ right into the metal if they hold too long or press too hard.

You can get various colourings for your anodizing, but they all scratch fairly easily. For a more durable coating you would get a “hard anodizing”. Someone said it before but I’ll say again make sure you have them cover up any area where you don’t want build up… like threads and whatnot.

“Hard anodizing is a term used to describe anodic coatings with surface hardness and/or abrasion resistance as their primary characteristic. Great for surface to surface sliding with low loads The color of the natural anodic coating depends on the alloy and the coating thickness. e.g. 6061 has a tan or gray color which darkens to almost black at .003”; 6063 has an amber shade which darkens to bronze. Both are considered clear. After hard anodizing surfaces may be sealed in boiling distilled water, sodium dichromate solution, dewatering oil, wax or PTFE solutions

Class 1: Not dyed or pigmented.

Class 2: Dyed. (Specify color on Drawing).
Hard anodic oxide coatings find application in the engineering industry for components which require a very wear resistant surface. " Flash" hard anodize may be used instead of conventional anodize for corrosion resistance."